After detecting signals possibly from the black box of the missing Malaysian plane, China’s search vessels failed to find any confirmed clues Sunday to conclusively establish that the pings are from the MH370.

Vessels of China’s ministry of transport searching for the missing passenger jet have searched a total of 136,000 square kilometers by mid- Sunday, Zhuo Li, an official with the China Maritime Search and Rescue Center, said.

The center had mobilised 62 merchant ships for their assistance in the search, he said.

Haixun 01 of the ministry and two Navy vessels continued the underwater search in southern Indian Ocean, three other ships were searching on the water surface. Two other vessels were searching in eastern Indian Ocean, Zhuo was quoted by official Xinhua news agency as saying.

China pressed 18 vessels, eight helicopters and three fixed-wing aircraft to trace the plane missing since March 8 along with 239 people on board.